Means for the production of long continuous electric arcs.



0. SGHUNHERR & J. HESSBERGER.

MEANS FOR THE PRODUCTION OF LONG CONTINUOUS ELECTRIC ARCS.

APPLICATION FILED OCT. 17, 1912.

Patented Ma 5, 1914.

UNITED sT rns natrEnT OFFICE.

o'r'ro sononnnnn, or nnnsnnn-sr'nrnsnn. GERMANY, AND JOHANNESnnssnnnonn,

or cmusrmnsann, nonwnx assieuons TO 'NonsK HYDRO-EILEKTRISK KVAEL- vsTonAK rInsnnsKAB, OF CHRISTIANIA,

NORWAY. A CORPORATION OF NORWAY.

MEANS THE PRODUCTTON OF LONG CONTINUOUS ELECTRIC ARCS.

Specification of Letters Patent.

Patented May 5,, 1914.

Original application filed May 18, 1910, Serial No. 562,097. Divided andthis application filed October 17, 1912. Serial No. 726,370. 1

, To all whom it m (11 concern Be itknown that'we, O'r'ro 'SGHiNHnnR andJOHANNES Hnssnnnonm; sub ects-"of-i the King of Saxonyfand the King ofPrussia, respectlvely, res1d1ng,respect1 vely, at Dres- No. 562,097, thepresent specification and "claim being a division of the same pursuantto the requirement of the Patent Office.

In the specification of Letters Patent No. 930238-we have described theproduction of long stable electric arcs by causing an arc to spring froman insulated electrode connected with one pole ofa source of electricityand situated at, or toward, one end of a long tube, or passage, thetube, or passage, itself being either connected with the other pole ofthe source of electricity, or containing at, or toward, the other endthereof, a second electrode connected with the other pole of the sourceof electricity, while at the same time a current of air, or other gas,oi gases, is passed though the'tube, or passage, with such velocity thata long and steadily burning electric arc is produced and maintainedwithin the said tube, or passage. The

,said specification discloses, for the first time,

a new principle, namely surrounding along electric arc with a layer vofnon-conducting fluid and maintaining this layer of fluid in such acondition that it is easier for the arc to continue in the position inwhich it'is burning than for it to spring through the layer ofsurrounding fluid. In order to bring about this condition, itisnecessary that the layer of gas (which we will hereinafter, for brevity,refer to as air, although other gas, under which term we include-agaseous mixture may be used in carrying out this invention). should notbe allowed to become so hot that it is capable of conductingelectricity, or at all events that it should not reach thishightemperature until it arrives at a point in the tube, or passage(which we will hereinafter, for brevit-yga'efer to as the tube) where itis desired thatthe arc should pass through the layer to the secondelectrodeor its equiyalent.

A particular method of carrying outthe principle set forth consists, asdescribed in the aforesaidspecification, in passing a current of. a r inone direction through the tube, @111 which thearc 1s produced,commencing at a pointeither below, or at a short distance.

abo \-'e,the insulated electrode. It is also preferablgaccording to thesaid specification,-that the air should be passed intothe tube with atangential, or rotatory motion.

The specification of Letters Patent No. 976,002 describes the production.of stable electric varcs :by means of two tubes, ,each

provided with an insulated electrode and leading into a common space.Air is blown past each electrode into the respective tube and 1s ledaway from the common-space,

while the arcs produced may join in the common space and form onecontinuous arc. :In Figure 3 of the drawings accompanying the last-namedspecification the two tubes are shown parallel to oneanother, but thespecificationdoes not restrict the arrangement to this, particularposition, as the two tubes may be placed end on to one another so thatone, straight continuous arc isobtained between two insulatedelectrodes, air being blown past each electrode and bein withdrawn fromthe tube at, or near, themi part thereof. \Ve have discovered thatinstead of the airpassing through the tube as described in the saidspecification, the arc can also be produced and maintained with certainadvantages it the air be made to pass through the tube or throughdifi'erent through the partsiof the apparatus which act as electrodes,or these, variatlons can be combined so that air is introduced 1nto thetube at each of the two ends thereof and passes along the interior walltoward the the mid part and then reverses itscourse so as to pass backalong the arc toward each of the two ends of the tube again.

When carrying out this invention we prefer to impart to the air, or topart of the air, entering the tube a tangential, or rotatory, motion,for instance such as is described in the aforesaid specification ofLetters Patent No. 930,238, andit is also generally advisable to coolthe openings through which the hot gases are removed from the tube. Thetubes which can be used in carrying out this invention may be variouslyshaped, for instance the tube containing the arc can be a long cylinder,or a short tube, or passage, of a diameter greater than its length.

We prefer generally to surround the tube containing the electric arcwith a second tube and to pass the air through the space between the twotubes before allowing it to enter the inner tube, so that in this waythe temperature of the inner tube is lowered and the air becomespreheated before entering the inner tube and consequently a highertemperature of the arc is admissible within the inner tube than would bethe case if no such preheating took place. VV-hen, according to thisinvention, the air passes along the interior wall of the tube and thenback again immediately surrounding the arc, a further advantage isattained, because heat is able to pass directly from the air immediately surrounding the arc to that which is moving in the oppositedirection along the interior wall of the tube, and the transference ofheat is greater because there is no intermediate wall through which theheat has to pass and since the hottest air does not come-into contactwith the wall of the tube a much higher temperature of the arc can beemployed within the tube than would be the case if the temperature ofthe arc had to 1 be restricted to prevent the material of which the tubeis made from being injured. When the air is led into the tube at one endonly and the gases are removed at the same end, the tube can becone-shaped the entrance and exit being at the larger end of the cone. 7

If desired, instead of introducing the whole supply of air into the tubein the manner hereinbefore' described, it can be introduced partly insuch manner and partly in any other suitable way, for insta'nceasdescribed in the specification of the aforesaid Letters Patent No.930,238.

The electrodes employed in carrying out the process according to thisinvention can be of various shapes. For instance they can be rod-shaped,as described in the aforesaid specification of Letter Patent No.930,238,

or they can be formed like a ring, and the end of the arc cancontinually move around the ring.

We give the following ways as examples of how this invention can beperformed in practice, referring to the accompanying drawing, but theinvention is not limited to these examples.

The drawing represents a vertical section of an apparatus suitable foruse according to this invention, showing how the electric arc can beproduced and how the gas is caused to pass inthe desired direction ordirections.

In the arrangement shown in the figure, two tubes are employed, namelyan upper one K, of inverted funnel shape, partly entering a lower tube Bso that there is a small ring-shaped opening r between them and throughthis opening the air is passed with a suitable velocity into the lowertube R, the said air passing down the interior of the wall thereoftoward the electrode which is situated at the lower end of the said tubeR, and then taking a course in'the opposite direction. as indicated bythe arrows, and passing away through the upper tube K.

The drawing illustrates the use of a coneshaped lower tube R which isinsulated from the rest or" the apparatus, the air passing in throughthe opening 7' bet-ween the tubes K and B into the lower tube, down theinterior inclined wall thereofand then upward surrounding the axis. Ifdesired, air can also be introduced at the lower end of the said lowertube R as illustrated by the arrow. When such an apparatus is used thereis a tendency for the end of the arc to describe a circular path aroundthe inner wall of the cone-shaped tube R.

I1n the figure L represents insulating mater1a What we claim is:

An apparatus of the kind described comprising a conical tube'connectedwith one pole of a course of electricity another pole insulated fromsaid tube. means for passing a current of gas into the tube at each endthereof and means for withdrawing the whole of the gas at one endthereof so that th gas entering at one end of the said conii cal tubepasses along the tube and reverses its course leaving at 01' near theend at which it entered the said tub.

OTTO SCH NHERR. J OHANNES HESSBERGER. Witnesses as to the signature ofOtto Schonherr: PAUL AREAS,

ARTHUR GUBE. Witnesses as to the signature of Johannes Hessberger:

P. BIRKELAND, T. V

ESTLY.

